Contrast between ancient ways of plowing with horses and modern ways using tractors, in Morocco

Group of workers walk beside a farmer plowing a field with a disc cultivator pulled by a D6 Caterpillar diesel tractor. The manual workers appear to be discarding clumps of grass or other undesired material. In contrast, two other farmers are seen plowing nearby using primitive wooden plows pulled by horses. One of them stops to repair his wooden plow, striking it with a stone to tighten it.